Cell-free fetal DNA screening in the USA: a cost analysis of screening strategies.

OBJECTIVES: To determine whether implementation of primary cell-free fetal DNA (cffDNA) screening would be cost-effective in the USA and to evaluate potential lower-cost alternatives. METHODS: Three strategies to screen for trisomy 21 were evaluated using decision tree analysis: 1) a primary strategy in which cffDNA screening was offered to all patients, 2) a contingent strategy in which cffDNA screening was offered only to patients who were high risk on traditional first-trimester screening and 3) a hybrid strategy in which cffDNA screening was offered to all patients ≥ 35 years of age and only to patients < 35 years who were high risk after first-trimester screening. Four traditional screening protocols were evaluated, each assessing nuchal translucency (NT) and pregnancy-associated plasma protein-A (PAPP-A) along with either free or total beta-human chorionic gonadotropin (ß-hCG), with or without nasal bone (NB) assessment. RESULTS: Utilizing a primary cffDNA screening strategy, the cost per patient was 1017 US$. With a traditional screening protocol using free ß-hCG, PAPP-A and NT assessment as part of a hybrid screening strategy, a contingent strategy with a 1/300 cut-off and a contingent strategy with a 1/1000 cut-off, the cost per patient was 474, 430 and 409 US$, respectively. Findings were similar using the other traditional screening protocols. Marginal cost per viable case detected for the primary screening strategy as compared to the other strategies was 3-16 times greater than the cost of care for a missed case. CONCLUSIONS: Primary cffDNA screening is not currently a cost-effective strategy. The contingent strategy was the lowest-cost alternative, especially with a risk cut-off of 1/1000. The hybrid strategy, although less costly than primary cffDNA screening, was more costly than the contingent strategy.

Drosophila modifier screens to identify novel neuropsychiatric drugs including aminergic agents for the possible treatment of Parkinson's disease and depression.

Small molecules that increase the presynaptic function of aminergic cells may provide neuroprotection in Parkinson's disease (PD) as well as treatments for attention deficit hyperactivity disorder (ADHD) and depression. Model genetic organisms such as Drosophila melanogaster may enhance the detection of new drugs via modifier or 'enhancer/suppressor' screens, but this technique has not been applied to processes relevant to psychiatry. To identify new aminergic drugs in vivo, we used a mutation in the Drosophila vesicular monoamine transporter (dVMAT) as a sensitized genetic background and performed a suppressor screen. We fed dVMAT mutant larvae ∼ 1000 known drugs and quantitated rescue (suppression) of an amine-dependent locomotor deficit in the larva. To determine which drugs might specifically potentiate neurotransmitter release, we performed an additional secondary screen for drugs that require presynaptic amine storage to rescue larval locomotion. Using additional larval locomotion and adult fertility assays, we validated that at least one compound previously used clinically as an antineoplastic agent potentiates the presynaptic function of aminergic circuits. We suggest that structurally similar agents might be used to development treatments for PD, depression and ADHD, and that modifier screens in Drosophila provide a new strategy to screen for neuropsychiatric drugs. More generally, our findings demonstrate the power of physiologically based screens for identifying bioactive agents for select neurotransmitter systems.

Elevated first trimester PAPP--a is associated with increased risk of placenta accreta.

OBJECTIVES: The objective of this article is to determine whether there were differences in first trimester serum analytes between cases of placenta previa with and without accreta. METHODS: Cases of placenta previa in which the patient had first trimester aneuploidy screening were identified. Pregnancy-associated plasma protein A (PAPP-A) and free beta human chorionic gonadotropin (fbhCG) MoMs were compared with those with an accreta. Accreta cases were also compared with published distributions to determine significance and to develop likelihood ratios based on MoM values. RESULTS: Eighty-two cases of previa were identified, including 16 with a histological diagnosis of placenta accreta. The median PAPP-A MoM of 1.68 in accreta was significantly greater than that of 0.98 in non-accreta (P = 0.002). For fbhCG, the median MoM was 1.00 and 1.01 in accreta and non-accreta, respectively. Of the 16 patients with accreta, 14 (87.5%, 95% confidence interval: [61.6%, 98.4%]) had PAPP-A MoM above 1.0. Six of 16 (37.5%) accreta cases were above the 90th percentile of the unaffected distribution. The likelihood ratios for accreta were 0.5, 2.0, and 3.0. PAPP-A MoMs were 0.19, 2.11, and 4.27, respectively. CONCLUSIONS: First trimester PAPP-A levels may be useful in identifying pregnancies at high risk for placenta accreta. Larger studies could incorporate both clinical and biochemical data into a risk algorithm.

p53 is required for brown adipogenic differentiation and has a protective role against diet-induced obesity.

Proper regulation of white and brown adipogenic differentiation is important for maintaining an organism's metabolic profile in a homeostatic state. The recent observations showing that the p53 tumor suppressor plays a role in metabolism raise the question of whether it is involved in the regulation of white and brown adipocyte differentiation. By using several in vitro models, representing various stages of white adipocyte differentiation, we found that p53 exerts a suppressive effect on white adipocyte differentiation in both mouse and human cells. Moreover, our in vivo analysis indicated that p53 is implicated in protection against diet-induced obesity. In striking contrast, our data shows that p53 exerts a positive regulatory effect on brown adipocyte differentiation. Abrogation of p53 function in skeletal muscle committed cells reduced their capacity to differentiate into brown adipocytes and histological analysis of brown adipose tissue revealed an impaired morphology in both embryonic and adult p53-null mice. Thus, depending on the specific adipogenic differentiation program, p53 may exert a positive or a negative effect. This cell type dependent regulation reflects an additional modality of p53 in maintaining a homeostatic state, not only in the cell, but also in the organism at large.

Impact of nuchal translucency credentialing by the FMF, the NTQR or both on screening distributions and performance.

OBJECTIVE: In the USA, both The Fetal Medicine Foundation (FMF) and the Nuchal Translucency Quality Review Program (NTQR) have operated education, review and credentialing for physicians and sonographers for the measurement of nuchal translucency (NT). We sought to assess differences in the distribution of NT measurements based upon the system from which the operator obtained their education, review and credentialing. METHODS: 398 311 NT measurements by 1541 sonographers who had performed ≥ 50 exams from July 2008 to June 2010 were grouped by organization. Differences between grouped measurements were assessed using analysis of variance of log(10) NT multiples of the median (MoM), with sonographer and organization as factors. RESULTS: MoM values were significantly lower (P ≤ 0.001) and SD was significantly higher (P < 0.001) for the NTQR group compared with the FMF group or those sonographers credentialed by both. The percentage of individuals with negative bias ≥ 10% was greater for the NTQR group (P < 0.001). The difference was less but still significant (P = 0.009) when bias was adjusted for by the overall median for the organization. CONCLUSIONS: Although NT MoM measurements were significantly lower and had a wider variance when obtained by the NTQR group, our data cannot distinguish between bias in training or the attributes of the participating sonographers in each program. With these large numbers, it is unlikely that patient characteristics could explain the discrepancy in distributions. Ongoing efforts to monitor sonographer performance with remediation for poor performers may reduce discrepancies between organizations.

A simple assay to study social behavior in Drosophila: measurement of social space within a group.

We have established a new simple behavioral paradigm in Drosophila melanogaster to determine how genes and the environment influence the behavior of flies within a social group. Specifically, we measure social space as the distance between two flies. The majority of Canton-s flies, regardless of their gender, are within two body lengths from each other. Their social experience affects this behavior, with social isolation reducing and mating enhancing social space respectively, in both males and females. Unlike several other social behaviors in the fly, including the formation of social groups themselves (a well-described behavior), social space does not require the perception of the previously identified aggregation pheromone cis-vaccenyl acetate. Conversely, performance of the assay in darkness or mutations in the eye pigmentation gene white increased social space. Our results establish a new assay for the genetic dissection of a fundamental mode of social interaction.

Psychotropic medication use and risk of adverse cardiovascular events in women with suspected coronary artery disease: outcomes from the Women's Ischemia Syndrome Evaluation (WISE) study.

OBJECTIVE: This study investigated the relation between psychotropic medication use and adverse cardiovascular (CV) events in women with symptoms of myocardial ischaemia undergoing coronary angiography. METHOD: Women enrolled in the Women's Ischemia Syndrome Evaluation (WISE) were classified into one of four groups according to their reported antidepressant and anxiolytic medication usage at study intake: (1) no medication (n = 352); (2) anxiolytics only (n = 67); (3) antidepressants only (n = 58); and (4) combined antidepressant and anxiolytics (n = 39). Participants were followed prospectively for the development of adverse CV events (for example, hospitalisations for non-fatal myocardial infarction, stroke, congestive heart failure and unstable angina) or all-cause mortality over a median of 5.9 years. RESULTS: Use of antidepressant medication was associated with subsequent CV events (HR 2.16, 95% CI 1.21 to 3.93) and death (HR 2.15, 95% CI 1.16 to 3.98) but baseline anxiolytic use alone did not predict subsequent CV events and death. In a final regression model that included demographics, depression and anxiety symptoms, and risk factors for cardiovascular disease, women in the combined medication group (that is, antidepressants and anxiolytics) had higher risk for CV events (HR 3.98, CI 1.74 to 9.10, p = 0.001 and all-cause mortality (HR 4.70, CI 1.7 to 2.97, p = 0.003) compared to those using neither medication. Kaplan-Meier survival curves indicated that there was a significant difference in mortality among the four medication groups (p = 0.001). CONCLUSIONS: These data suggest that factors related to psychotropic medication such as depression refractory to treatment, or medication use itself, are associated with adverse CV events in women with suspected myocardial ischaemia.

Major life changes before and after the onset of chronic daily headache: a population-based study.

Chronic daily headache (CDH), when defined as > or = 15 headache days per month, affects 3-5% of the adult population. Major life changes are putative precipitating events for onset of chronic pain, including chronic headache. This study compared the occurrence of specific life events between CDH cases and episodic headache controls in a community sample. CDH cases (180+ headache days per year: n = 206) and episodic headache controls (2-104 headache days per year: n = 507) were identified from a randomly selected adult US population. Subjects were interviewed about the occurrence of certain major life changes or events (change of residence, employment status, marital status, related to their children, deaths of relatives or close friends, and 'extremely stressful' ongoing situations) occurring in a defined time period. Events that occurred during the same year or year before frequent headache onset in cases or in an equivalent time period in controls were considered to be antecedent events. Those that occurred after this time were considered subsequent events. Compared with episodic headache controls, CDH cases had more major life changes in the year before or same year as CDH onset. After adjusting for age, gender, headache type and year of event, the odds of CDH increased additionally with each antecedent event [odds ratio (OR) 1.20 (1.1, 1.3), P < 0.001], but not with subsequent events [OR 0.94 (0.8, 1.1), P < 0.4]. In secondary analyses, the association between antecedent events and CDH was significant only for the approximately half of CDH cases who were aged >/= 40 years [OR 1.33 (1.2, 1.50) vs. OR 1.04 (0.9, 1.2), P < 0.05 for interaction by age]. These results suggest that major life changes are associated with the onset of chronic daily headache, particularly in middle age.

Genetic sonography after first-trimester Down syndrome screening.

OBJECTIVE: Approximately 90% of Down syndrome cases are detected during first-trimester screening. We aimed to determine the potential effectiveness of second-trimester genetic sonography as a sequential screen for Down syndrome. METHODS: In this simulation study, published statistical parameters for first-trimester free beta-human chorionic gonadotropin, pregnancy-associated plasma protein-A and nuchal translucency thickness, and second-trimester ultrasound markers (nuchal fold, hyperechoic bowel, short humerus, short femur, echogenic intracardiac focus, pyelectasis and major abnormality) were used to model the effectiveness of second-trimester genetic sonography combined with first-trimester screening. RESULTS: First-trimester combined screening alone resulted in a detection rate of 88.5% with a 4.2% false-positive rate. A follow-up genetic ultrasound examination in which only one sonographic marker was found and previous results were not taken into account would detect an additional 8% of Down syndrome cases for an additional false-positive rate of 13.2%. Using individual marker likelihood ratios to modify the first-trimester risk for screen-negative patients, genetic sonography detected an additional 6.1% of Down syndrome cases for an additional 1.2% false-positive rate, giving a total detection rate of 94.6% and a total false-positive rate of 5.4%. In a contingent protocol, in which genetic sonography would be performed only for patients with a first-trimester risk of between 1/300 and 1/2500, the detection rate was 4.8% and the false-positive rate was 0.7%, giving a total detection rate of 93.3% and a total false-positive rate of 4.9%. CONCLUSION: Second-trimester genetic sonography, if used properly, can be an effective sequential screen following first-trimester Down syndrome screening. Further studies on the role of the genetic sonogram as a follow-up to first-trimester combined screening are warranted.

Cell-type-specific limitation on in vivo serotonin storage following ectopic expression of the Drosophila serotonin transporter, dSERT.

The synaptic machinery for neurotransmitter storage is cell-type specific. Although most elements of biosynthesis and transport have been identified, it remains unclear whether additional factors may be required to maintain this specificity. The Drosophila serotonin transporter (dSERT) is normally expressed exclusively in serotonin (5-HT) neurons in the CNS. Here we examine the effects of ectopic transcriptional expression of dSERT in the Drosophila larval CNS. We find a surprising limitation on 5-HT storage following ectopic expression of dSERT and green fluorescence protein-tagged dSERT (GFP-dSERT). When dSERT transcription is driven ectopically in the CNS, 5-HT is detectable only in 5-HT, dopamine (DA), and a very limited number of additional neurons. Addition of exogenous 5-HT does not dramatically broaden neuronal storage sites, so this limitation is only partly due to restricted intercellular diffusion of 5-HT. Furthermore, this limitation is not due to gross mislocalization of dSERT, because cells lacking or containing 5-HT show similar levels and subcellular distribution of GFP-dSERT protein, nor is it due to lack of the vesicular transporter, dVMAT. These data suggest that a small number of neurons selectively express factor(s) required for 5-HT storage, and potentially for function of dSERT.

Geometric morphometric analysis of shape outlines of the normal and abnormal fetal skull using three-dimensional sonographic multiplanar display.

OBJECTIVES: Geometric morphometric analysis has been used to quantify differences in biological shapes. Cranial irregularities are described in anomalous fetuses but are qualitative and ill-defined. Our goal was to apply geometric morphometric statistical analysis using three-dimensional (3D) multiplanar display to quantify shape differences in normal and abnormal fetal skulls. METHODS: This was a retrospective pilot study of mid-trimester patients undergoing ultrasonography. 3D multiplanar display using spatial rotation was used to identify landmarks in coronal and transverse planes to establish a consistent fetal facial profile. Outline coordinates of the brow were determined by blinded examiners using computer software. Elliptical Fourier analysis (EFA) was used to obtain sets of functional coefficients. An atypicality index (AI) was determined from retained principal component (PC) scores. An AI > 95(th) percentile of the expected distribution defined outliers. RESULTS: Outlines were successfully identified in 38 patients (six abnormal). Using the AI, there were three outliers, all from abnormal fetuses (trisomy 18, trisomy 21, and campomelic dysplasia). Two fetuses with trisomy 21 and one with an unbalanced translocation had normal atypicality indices. CONCLUSIONS: 3D multiplanar display and geometric morphometric analysis enable quantification of fetal skull shape. An abnormal skull shape was identified in two of four aneuploid fetuses and no normal ones. Geometric morphometric analysis represents a promising new quantitative modality which, when applied with 3D sonographic multiplanar display, may be used to more objectively analyze fetal malformation. Larger prospective trials are needed to refine the technique and improve reproducibility.

Overexpression of the Drosophila vesicular monoamine transporter increases motor activity and courtship but decreases the behavioral response to cocaine.

Aminergic signaling pathways have been implicated in a variety of neuropsychiatric illnesses, but the mechanisms by which these pathways influence complex behavior remain obscure. Vesicular monoamine transporters (VMATs) have been shown to regulate the amount of monoamine neurotransmitter that is stored and released from synaptic vesicles in mammalian systems, and an increase in their expression has been observed in bipolar patients. The model organism Drosophila melanogaster provides a powerful, but underutilized genetic system for studying how dopamine (DA) and serotonin (5HT) may influence behavior. We show that a Drosophila isoform of VMAT (DVMAT-A) is expressed in both dopaminergic and serotonergic neurons in the adult Drosophila brain. Overexpression of DVMAT-A in these cells potentiates stereotypic grooming behaviors and locomotion and can be reversed by reserpine, which blocks DVMAT activity, and haloperidol, a DA receptor antagonist. We also observe a prolongation of courtship behavior, a decrease in successful mating and a decrease in fertility, suggesting a role for aminergic circuits in the modulation of sexual behaviors. Finally, we find that DMVAT-A overexpression decreases the fly's sensitivity to cocaine, suggesting that the synaptic machinery responsible for this behavior may be downregulated. DVMAT transgenes may be targeted to additional neuronal pathways using standard Drosophila techniques, and our results provide a novel paradigm to study the mechanisms by which monoamines regulate complex behaviors relevant to neuropsychiatric illness.

Measurement of nasal bone length at 11-14 weeks of pregnancy and its potential role in Down syndrome risk assessment.

OBJECTIVES: To assess the feasibility of measuring nasal bone length in first-trimester pregnancy and to confirm if the absence of a fetal nasal bone is a marker for Down syndrome. METHODS: Fetal nasal bone assessment was attempted in 1089 consecutive singleton pregnancies between 11 and 14 weeks' gestation. All ultrasound examinations were performed transabdominally in three separate centers. If the nasal bone was present, nasal bone length was measured. RESULTS: Nasal bone assessment was successfully achieved in 1027 of 1089 (94.3%) ultrasound examinations. Within this group nasal bone was absent in 10 of 1000 (1.0%) unaffected cases, 10 of 15 (66.7%) Down syndrome cases and 5 of 12 (41.7%) cases with other pathological conditions. Regression analysis showed a significant increase (P < 0.0001) in nasal bone length from 2.48 mm at a crown-rump length of 45 mm to 3.12 mm at a crown-rump length of 84 mm. The nasal bone length in the five cases of Down syndrome in which the nasal bone was present was less than the median measurement of unaffected cases. Using modeling, the combination of nasal bone with maternal age, nuchal translucency, free beta-human chorionic gonadotropin (hCG) and pregnancy associated plasma protein-A (PAPP-A) achieved a detection rate of 95% with a false-positive rate of 2.9%. At a fixed 1% false-positive rate, the detection rate was 91%. CONCLUSIONS: Absence of the nasal bone can be used as a marker for Down syndrome in the first trimester of pregnancy. Inclusion of the nasal bone in the current first-trimester screening protocol along with nuchal translucency, free beta-hCG and PAPP-A can achieve high detection at a very low false-positive rate. Large datasets are needed to confirm whether the measurement of nasal bone length provides additional benefits beyond the assessment of the presence or absence of the nasal bone.

Frequency and clinical consequences of extremely high maternal serum PAPP-A levels.

A multicentre study was carried out to determine the frequency and clinical consequences of extremely high maternal serum pregnancy-associated plasma protein (PAPP)-A. There was a total of 79 pregnancies with PAPP-A exceeding 5.0 multiples of the gestation-specific median in a series of 46 776 pregnancies tested (0.2%) at the 7 collaborating centres. Five pregnancies were lost to follow-up, one miscarried and one with Noonan's syndrome was terminated. Of the remaining 72 that ended in a live birth, one infant had gastroschisis and five pregnancies had obstetric complications: pre-eclampsia, pregnancy-induced hypertension, gestational diabetes and two with growth retardation. Among women with high PAPP-A and no complications or adverse outcomes, there was no evidence of a substantial change in the levels of other Down syndrome markers or the extent of nuchal translucency. Three analytical methods were used to assay PAPP-A and yielded different frequencies of extremely high levels (0.05%, 0.4% and 0.6%) possibly owing to cross-reaction with another substance. We conclude that women with high PAPP-A can be reassured that there is no reason to suppose that the outcome of pregnancy will differ from those with normal levels, provided other markers are normal. If, as more centres move their Down syndrome screening practice to the first trimester, additional cases emerge with Noonan's syndrome or gastroschisis and raised PAPP-A, this advice will need to be modified.

Changes in heart rate and heart rate variability before ambulatory ischemic events(1).

OBJECTIVES: The aim of this study was to determine the time course of autonomic nervous system activity preceding ambulatory ischemic events. BACKGROUND: Vagal withdrawal can produce myocardial ischemia and may be involved in the genesis of ambulatory ischemic events. We analyzed trajectories of heart rate variability (HRV) 1 h before and after ischemic events, and we examined the role of exercise and mental stress in preischemic autonomic changes. METHODS: Male patients with stable coronary artery disease (n = 19; 62.1 +/- 9.3 years) underwent 48-h ambulatory electrocardiographic monitoring. Frequency domain HRV measures were assessed for 60 min before and after each of 68 ischemic events and during nonischemic heart rate-matched control periods. RESULTS: High-frequency HRV decreased from -60, -20 to -10 min before ischemic events (4.8 +/- 1.3; 4.6 +/- 1.3; 4.4 +/- 1.2 ln [ms(2)], respectively; p = 0.04) and further from -4, -2 min, until ischemia (4.4 +/- 1.3; 4.1 +/- 1.3; 3.7 +/- 1.2 ln [ms(2)]; p's < 0.01). Low frequency HRV decreases started at -4 min (p < 0.05). Ischemic events occurring at high mental activities were preceded by depressed high frequency HRV levels compared with events at low mental activity (p = 0.038 at -4 min, p = 0.045 at -2 min), whereas the effects of mental activities were not observed during nonischemic control periods. Heart rate variability measures remained significantly decreased for 20 min after recovery of ST-segment depression when events were triggered by high activity levels. CONCLUSIONS: Autonomic changes consistent with vagal withdrawal can act as a precipitating factor for daily life ischemia, particularly in episodes triggered by mental activities.

Effects of mental stress on coronary epicardial vasomotion and flow velocity in coronary artery disease: relationship with hemodynamic stress responses.

OBJECTIVES: This study examines the prevalence and hemodynamic determinants of mental stress-induced coronary vasoconstriction in patients undergoing diagnostic coronary angiography. BACKGROUND: Decreased myocardial supply is involved in myocardial ischemia triggered by mental stress, but the determinants of stress-induced coronary constriction and flow velocity responses are not well understood. METHODS: Coronary vasomotion was assessed in 76 patients (average age 59.9 +/- 10.4 years; eight women). Coronary flow velocity responses were assessed in 20 of the 76 patients using intracoronary Doppler flow. Repeated angiograms were obtained after a baseline control period, a 3-min mental arithmetic task and administration of 200 microg intracoronary nitroglycerin. Arterial blood pressure (BP) and heart rate assessments were made throughout the procedure. RESULTS: Mental stress resulted in significant BP and heart rate increases (p < 0.001). Coronary constriction (>0.15 mm) was observed in 11 of 59 patients with coronary artery disease (CAD) (18.6%). Higher mental stress pressor responses were associated with more constriction in diseased segments (rdeltaSBP = -0.26, rdeltaDBP = -0.30, rdeltaMAP = -0.29; p's < 0.05) but not with responses in nonstenotic segments. The overall constriction of diseased segments was not significant (p > 0.10), whereas a small but significant constriction occurred in nonstenotic segments (p = 0.04). Coronary flow velocity increased in patients without CAD (32.2%; p = 0.008), but not in patients with CAD (6.4%; p = ns). Cardiovascular risk factors were not predictive of stress-induced vasomotion in patients with CAD. CONCLUSIONS: Coronary vasoconstriction in angiographically diseased arteries varies with hemodynamic responses to mental arousal. Coronary flow responses are attenuated in CAD patients. Thus, combined increases in cardiac demand and concomitant reduced myocardial blood supply may contribute to myocardial ischemia with mental stress.